Any existing user apparatus (such as a mobile device) is usually equipped with a multiple or heterogeneous radio access interface, such as a Wi-Fi (wireless network) interface and a Long Term Evolution (LTE) interface and the like. Thus, a gateway for Multiple Radio Access Technology (Multi-RAT) service provided between base stations and a core network provides multiple network bandwidth aggregation service to improve network transmission speed. However, this is bound to affect the original communication protocols or connection mechanisms.
In the conventional art, in order to provide the Multi-RAT service the Internet Protocol (IP) address of the Multi-RAT gateway must be set in a small-cell base station or an access-point base station. For a user apparatus capable of Multi-RAT service, two segments of tunnel have to be established between the base station and the core network. For example, a first segment of the tunnel is between the small cell (or an access point) base station and the gateway, and a second segment of the tunnel is between the gateway and the core network. However, in this scenario all packets coming from the user apparatus will have to be transmitted to the core network through the two-segment tunnel by activating the gateway to provide additional services, thus delaying the processing performance and transmission speed of the packets of the user apparatus.